Plastic film mulch, normally in the nature of sheets of polyethylene several hundred or several thousand feet in length, is used extensively as a cultivation aid in large field operations in particular. However, a major problem exists with regard to the periodic necessity for removal of the film mulch.
Any attempt to rewind the film mulch for reuse would be highly impractical. As such, standard procedures involve the disposal of the used mulch. This disposal can involve a gathering and burning of the mulch which requires a large burning area and is clearly environmentally unacceptable. The mulch has also been loosely gathered and disposed of in landfills. However, landfill expenses and the decreasing availability of landfills, make this an increasingly less desirable solution. It has also been proposed that the mulch be stockpiled in the field or disced in. However, inasmuch as the film does not, in a practical sense, biodegrade, this solution would clearly have adverse effects on the soil and subsequent planting operations.
Another suggested solution to the problem of disposal of agricultural plastic film mulch proposes the stripping of the mulch from the field with the loose mulch transported to a central area for compacting. It has also been suggested that the mulch be directly gathered from the field by mobile hay balers. However, this has been found to be impractical as the sheet material, because of the lengths thereof and the tendency to stretch, wrap up with the operating mechanisms of the hay baler and produce severe malfunctioning.
The patent to Gouker et al, U.S. Pat. No. 3,181,455, issued May 4, 1965, is of interest in disclosing apparatus specifically for gathering and baling sheet material directly from the field. This apparatus is intended to gather endless lengths of film with the leading end of the film manually inserted through a guide ring, a forwardly spaced guide grommet, and a pair of rollers immediately forward of the grommet. The rollers automatically pull the film from the field and must be timed to the progress of the apparatus through the field. Several potential problems are noted with regard to the Gouker et al apparatus. Inasmuch as film mulch is normally provided with transverse cuts for drainage at approximately every 100 feet or so, there is a tendency for the sheets to tear or sever along these cut lines. This would particularly occur as the sheets are anchored by soil along the edges thereof, providing a resistance to the pulling of the film from the field. When the film is so severed, the Gouker apparatus must be stopped and the film again manually fed through the rather elaborate arrangement required by Gouker.
Another potential problem arising in that the automatic pulling of the film from the field does not provide for any effective means for removing soil and debris from the film before the film reaches the constricted areas of the guide ring, grommet ring and rollers, thus giving rise to the possibility of the equipment jamming. Thus, Gouker et al also does not present an optimum solution to film removal and disposal.